/* menuette.c -- menu techniques */
#include <stdio.h>

char get_choice(void);
char get_first(void);
int get_int(void);
void count(void);

int main(void) {
  int choice;
  void count(void);

  while ((choice = get_choice()) != 'q') {
    switch (choice) {
      case 'a':
        printf("Buy low, shell high.\n");
        break;
      case 'b':
        putchar('\a'); /* ANSI */
        break;
      case 'c':
        count();
        break;
      default:
        printf("Program error!\n");
        break;
    }
  }
  printf("Bye.\n");

  return 0;
}

void count(void) {
  int n, i;

  printf("Count how far? Enter an integer:\n");
  n = get_int();
  for (i = 1; i <= n; i++) printf("%d\n", i);
  while (getchar() != '\n') continue;
}

char get_choice(void) {
  int ch;
  printf("Enter the letter of your choice:\n");
  printf("a. advice\t\tb. bell\n");
  printf("c. count\t\tq. quit\n");
  ch = get_first();
  while ((ch < 'a' || ch > 'c') && ch != 'q') {
    printf("Please respond with a, b, c or q.\n");
    ch = get_first();
  }

  return ch;
}

char get_first(void) {
  int ch;

  ch = getchar();
  while (getchar() != '\n') continue;

  return ch;
}

int get_int(void) {
  int input;
  char ch;

  while (scanf("%d", &input) != 1) {
    while ((ch = getchar()) != '\n') putchar(ch);  // dispose of bad input
    printf(
        " is not an integer.\nPlease enter an integer value, such as 25, -178 "
        "or 3: ");
  }

  return input;
}
